The disclosure relates to a guide carriage for a linear roller bearing according to the description below.
Guide carriages for linear roller bearings permit a precisely guided linear movement under high loads. For this purpose, the guide carriage on which the load acts moves along a rectilinear guide rail. In order to reduce the friction in the event of simultaneously heavy transferable loads, generally four closed or endless rows of rollers revolve in corresponding roller tracks between the guide carriage and the guide rail. The guide rail is embraced by guide carriages, and therefore loads can be supported in all of the directions which are directed transversely with respect to the direction of movement.
In the guide carriage shown in document DE 10 2007 056 862 A1, two rows of rollers are provided in each case on both sides of the guide rail, thus preventing the guide carriage from lifting off the guide rail. What are referred to as deflecting pieces are inserted here in the interior of the guide carriage and serve in each case to deflect two rows of rollers. Two deflecting pieces in each case are inserted together into an end cap on the end side of the guide carriage, with two end caps being provided. The deflecting pieces each have curved deflecting tracks which are nested one in the other in what is referred to as an 0 arrangement and each form a section of a roller track.
Document DE 10 2010 049 943 A1 discloses a lubricating system for guide carriages of this type. The guide carriage here is supplied with lubricant which is guided via internal channels to orifices in the roller tracks, with the rollers running past said orifices.
In order to prevent the lubricant lines from draining when the guide carriage, and therefore the conveying of lubricant, are at a standstill, document DE 44 12 797 C2 proposes a lubricant-retaining device which is configured as a nonreturn valve. The disadvantage of this is that the nonreturn valve is arranged on an end side of the guide carriage and therefore spaced apart from the roller tracks. This leaves a lubricant line section between the nonreturn valve and the roller track that may drain and that first of all has to be filled again when resuming or restarting the lubrication.
Document DE 10 2010 049 944 A1 discloses elastic valve flaps in the vicinity of the lubricant line orifices into the roller tracks. Said valve flaps are formed in what is referred to as a deflecting plate which is provided between the respective end cap and a central main body of the guide carriage. The valve flaps are bent elastically and open up a path for lubricant when the latter and a is conveyed towards the valve flap. In this case, when the valve flap is closed, a U-shaped slot also remains, and, when low-viscosity lubricant is used, an amount of lubricant always passes through said slot.
Document EP 2 094 984 B1 discloses valves in the vicinity of the roller track as a lubricant-retaining means. The valves are arranged in the interior of the end cap which are fitted onto the end sides of the guide carriage. The valves consist of elastically bendable, tab-like elements which, in the conveying direction of the lubricant, open up a slot which is pressed shut in the opposite direction.
A disadvantage of the last-mentioned guide carriages is that the lubricant-retaining devices thereof are not sufficiently tight in the event of low-viscosity lubricant. Furthermore, lubricant-retaining devices of this type have manufacturing tolerances which result in a nonuniform opening behavior. In particular if the required lubricant quantity are intended to be minimized, a uniform behavior of all of the lubricant-retaining devices is important so that a uniform supply of all of the roller tracks with lubricant is ensured.
Accordingly, it is the object of the disclosure to provide a guide carriage for a linear roller bearing, the lubricant-retaining devices of which are improved.
This object is achieved by a guide carriage for a linear roller bearing with the features described below.